Tricycle frame



FIG. 1 is a front perspective view of a tricycle frame, showing the new design;

FIG. 2 is a perspective view from the left rear thereof illustrating saddle and handlebars in broken lines;

FIG. 3 is a perspective view from the left front top thereof;

FIG. 4 is a front elevation view thereof;

FIG. 5 is a side elevation view thereof; and,

FIG. 6 is a folded side elevational view thereof.

The broken line showing the handlebar, tricycle stem, seat tube, seat, wheels and axle is for the purpose of illustrating environmental structure for a tricycle frame and forms no part of the claimed design. 

CLAIM The ornamental design for a tricycle frame, as shown and described. 